Knor fastening device



17, 1940. HL J. MURPHY 7 7 2,215,243,

KNOB FASTENING DEVICE Fi led May 19, 1939- Invenflrrf Howard J Murpky.

Patented Sept. 17, 1940 2,215,24&

PATENT OFFICE KNOB FASTENING DEVICE.

Howard J Murphy, Greenwood,.Mass., assignor to United-Carr FastenerCorporation, Cambridge, Mass, a corporation of MassachusettsApplicationMay I9, 1939, Serial No. 274,565

3. Claims.

This invention relates to knobs and like. fastening installations andfasteners for thesame.

Referring to the drawing, in which I have illustrated a preferred. formof my invention:

Fig. 1 is a longitudinal sectional view through a knob member showing ashaft secured to the knob member by means of my improved fastenermember;

Fig. 2 is a side elevation of the fastener member shown in Fig. 1;

Fig. 3 is a front plan view of the fastener member shown in Fig. 2; and

Fig. 4 is a sectional view taken along the line 44 of Fig. 1 showing themanner in which the fastener is secured to the knob.

My invention relates to improvements in knob devices which may be of thetype used on radio dial panels or automobile instrument panels and isparticularly directed to an improved faso tener member adapted to bequickly and easily assembled with an article of manufacture such as acontrol knob of the type described for the purpose of detachablysecuring a shaft member in non-rotative relation to the knob.

Referring to the installation shown in Figs. 1 and 4, I have provided aknob I, which may be of plastic or other material, having a circularopening or bore 2 extending from an end face 3 into the body of theknob. My improved fastener member 4 is disposed in assembled relationwith the knob within the bore 2 and provides an eflicient means fordetachably securing a shaft member 5 to the knob. The shaft member 5'may be of the type adapted for connecting parts of automobile and radioapparatus with finger operative knob means disposed in operatingposition on a dial or instrument panel. The shaft 5 has a flat face 6adjacent its free end for cooperation with the fastener member in amanner to be described.

The fastener member a is preferably formed of one piece of spring metaland provides an elongated shaft-engaging bowed portion I. Integral withan end 8 of the bowed portion 1 I have provided a lip portion 9 flaredoutwardly to one side of the bowed portion for a purpose to be describedIntegral with an opposite end I0 of'the bowed portion I from that towhich the lip portion 9 is joined I have provided attaching means in theform of a spring tongue II. The spring tongue I I is bent laterally atan angle to the bowed portion I with the free end I2 of the tonguefacing substantially toward that end of the fastener having the lipportion 9. It will be noticed as that the spring tongue II isconstructed in such a, way" that the normal distance between edgesof thetongue at. the free end I2 thereof and points on the bowed portion I ina horizontal plane through the free end portion I2 is greater than thedistance between the chord of the bowed portion I with the opening 2when the fastener is in assembled relation with the knob and the pointof engagement of the free end portion I2 with the wall of the opening 2with the result that. at least one of the: edges of the free end of thetongue engages a wall of the opening 2 when the spring tongue is finallyseated within the opening, as shown in Fig. 1. Thus if either the a knobI or the fastener 4 is pulled relative to the other for the purpose ofseparating the parts, an edge of the free end of the tongue bites intothe wall of the bore and resists such separation as it tends to flattenunder stress. Assembly of the fastener member 4 with the knob member Iis a relatively simple matter and is carried out by moving the fastenermember into the opening 2 of the knob until the spring tongue I I abutsthe closed end I3 of the opening 2. When the fastener member is set infinal attached position within the bore of the knob, the spring tongueII is compressed slightly so as to frictionally engage the wall of thebore (Fig. 1) and thereby rigidly secure the parts together. At the sametime the free ends 8 and III of the bowed portion I engage the wall ofthe knob with the lip portion 9 extending outwardly away from the wall.When the shaft member is secured to the knob, the free end of the shaftis moved into the bore 2 between the outer surface I4 of the bowedportion I and the wall portion I5 of the opening 2 facing the surfaceI4. The distance between the surface I I at the most outwardlybowedportions of the portion I and the wall portion I 5 is relatively lessthan the diameter of the shaft through the hat face 6. Thus passage ofthe shaft member between the aforesaid parts causes the bowed portion 1to contract or flatten so as to permit the shaft to be extended into theknob. After the shaft has been moved into the knob a predetermineddistance, it is held-therein against the tension of the bowed portion Iengaging the flat surface 6 to force the shaft against the wall I5. Itwill be seen that the function of the lip portion 9 is to effect freeelongation of the bowed portion 1 when contracted by the shaft. Theshaft is now securely assembled in nonrotative relation to the knob andmay not be removed until sufficient relative pull pressure has beenexerted on either the knob or the shaft to cular opening therein in away to effect a satisfactory detachable fastening device for thepurposes described.

Although I have illustrated and described a preferred embodiment of myinvention, Ido. not Wish to be limited thereby because thescope of myinvention is best defined by the following H claims.

I claim: a

1. The combination with a shaft and an article of manufacture having abore into which one end of said shaft extends and a fastener memberhaving an elongated bowed portion disposed within said bore andresiliently engaging a side of said shaft for securing said shaft tosaid article, and a resilient attaching portion integral with said bowedportion adjacent to its innermost end and extending across the inner endof the shaft into engagement with the material of said article adjacentsaid bore for attaching saidfastener to said article. I

tion integral with an opposite end of said bowed portion from said freeend portion, said attaching portion being seated within said bore andextending across the inner end of said shaft into engagement with thematerial of said article adjacent said bore for attaching said fastenerto said article.

3. The'combination with a shaft and an article of manufacture having asingle circular bore only of a fastener member having an elongated bowedportion disposed within said bore and resiliently engaging a side ofsaid shaft for securing said shaft to said article, and a resilienttongue portion integral with one end of said bowed portion, said tongueportion being seated within said bore and engaging the material of saidarticle adjacent said bore at a side opposite to the bowed portion forattaching said fastener to said article.

HOWARD J. MURPHY.

